Dry process beneficiation apparatus



March 15, 1960 M. E. MENCIMER 2,928,542

DRY PROCESS BENEFICIATION APPARATUS Filed Oct. 4, 1957 2 SheetS -Sheet 1 m r-v -1 HEAVY INVENTOR. Myron E. Menc/mer ATTORNEYS March 15, 1960 M. E. MENCIMER DRY PROCESS BENEFICIATION APPARATUS 2 Sheets-Sheet 2 Filed Oct. 4, 1957 INVE NTOR.

Myron E. Menc/mer BY my wwni ATTORNEYS United Sttes Patent Ofiice 2,928,542 DRY PROCESS BENEFlCIATION Myron E. Mencimer, Denver Colo.

Application October 4, 1957, Serial No. 688,813

Claims. (Cl. 209-45) This invention relates to dry process ore separators, and more particularly to pneumatic beneficiationapparatus for separating mineral values from their natural ores in a dry state, especially the beneficiation of such light mineral values as mica, asbestos, etc.

The'apparatus of the present invention provides apparatus for the economical and efficient dry beneficiation of the natural ores which have been sufliciently ground or crushed to provide a separation of mineral values from accompanying gangue. The invention, also, provides an effective method for the dry beneficiation of natural ores. The method generally includes passing the finely divided ore onto a downwardly sloped foraminous member which is traveling in an upward direction. Suction is applied to the underneath side of the foraminous surface and the lighter components of the ore are retained on the surface and carried beyond the suction for discharge from the surface, while the heavier components fall downwardly along the surface and thus separate from light fractions. In a simple, effective embodiment of the invention a horizontally disposed cylindrical member having a foraminous surface is rotated in a direction to provide a downwardly sloped, upwardly moving surface adjacent the apex of the surface. Suction is applied to a portion of the cylinder below the crown or apex of the cylinder at about the point of introduction of the crushed ore onto the surface of the cylinder. Generally the ore is directed onto the surface from a feed chute launder providing short gravitational fall, and the direction of fall of the ore is preferably opposedto the direction of movement of the foraminous surface of the cylinder. To provide an eflicient and effective device a series of such cylinders may be used in a stepwise arrangement. Such a series of cylinders may be vertically spaced so that a gravitational flow of ore from cylinder to cylinder may be used. Such an arrangement provides an effective multiple step beneficiation process, in which the first step removes a substantial quantity of the lighter components of the ore and subsequent cylinders remove substantially all of the remaining amount of light components from the heavier components of the ore.

It is, therefore, among the objects and the advantages of the invention to provide apparatus for the dry beneficiation of the mineral values from their natural ores, which apparatus includes a pneumatic system arranged to provide dry separation of light components of the crushed ore from its heavier components. The apparatus provides a downwardly sloped, upwardly moving foraminous surface against which a stream of finely divided ores is directed, and a suction beneath at least part of the surface holds light components of the ore onto-the surface for a sufiicient period of time to permit separation of the light components from the heavier components. A foraminous, horizontal cylinder 'is provided with suction applied to the'underside of the cylinder at one point for separating and holding light components from the heavier components of an ore, 'and the light components may be subsequently removed by an airblast chute.

2 v blown through the surface. A plurality of vertically disposed cylinders may be so interconnected as to provide an etficient multiple stage dry beneficiation apparatus.

These and other objects of the invention may be readily ascertained by referring to the following description and appended illustrations in which: h

Figure 1 is a schematicflow sheet of a multiple stage separator according to the invention;

Figure 2 is an enlarged side elevational view of a stage separator;

Figure 3 is an enlarged perspective view of one form of a suction system of the dry separator according to the invention;

Figure 4 is a perspective view of one form of foraminous cylinder, illustrating 'means'for supporting and ro-' tating the same; v f

- Figure 5 is a side elevational view of the device of Figure 4; I y

Figure 6 is a detailed view ofa suction tube for use in a foraminous cylinder according tothe invention;

Figure 7 is a front elevation of 'a three stage separator, in partial broken away view, illustrating a general equipment set up; and

Figure 8 is a detailed and suction system; t

The enlarged detail illustrated in Figure 2 shows a single stage separator, and since each of the stages of a multiple stage machine will be constructed in substantially the same manner, description of the single stage will be suflicient for all the stages of such machine. A cylindrical screen member'l, which is arranged substantially horizontal and mounted for rotary movement in the direction indicated, encloses a suction tube'2 which is substantially non-rotatable, except that it may be mounted so as to be rotated through a small arc'for adjustment purposes. The suction tube has a slot 3 extending substantially along a major portion thereof, and the single perspective of a modifiedjcylinder slot 3 has upstanding sidewalls 4. The screen 1 is closely 1 adjacent the upstanding wall 4 so that when suction is applied on the tube 2 air will be drawn from the outside through the screen and through the slot rather than from around the walls and the space inside the screen tube 1. Suction when used in this application refers to a pressure difierential created by lowering the air pressure in the tube 2, as by interconnecting the tube with the intake or suction side of an air pump. An elongated tube or pipe 5 extends along the length of the screen and is supplied by a supply of air under superatmospheric pressure, and the pipe 5 contains a series of holes 6, or a narrow slot, mounted adjacent to screen 1 in position to blow ofi any material adhering to the screen. A discharge chute 7 is mounted adjacent the air tube '5 with sufiicient back and side walls to catch material falling from or blown from the screen. The material discharged from the screeninto the discharge 7 falls into a collector tube 8 which has a slot 9 interconnecting the tube with the discharge 7. By having one end of the tube 8 closed suction can be applied to the other end, and the light material collected from the screen may be withdrawn from the tube 8, illustrated in Figure 7, described below.

A feed launder or chute 15 is adjustably disposed above the screen 1, and its discharge end.16 is spaced so that ground ore discharging from the chute 15 falls on the screen 1 above the slot 3. Abaflie box 18 is disposed in the chute 15 and is adjustable along the length of the chute to provide an opening 19 for controlling the rate flow of ore from the sheet. A thumbscrew 20 provides means for holding the baffle box 18 in position in the The chute 15 has a supporting arm 21 mounted on an upright member 22 of a frame (not shown) to 7 provide an adjustable support for the chute. The chute 15 is adjustable bothtoward and away from the screen Patented Mar. 15, 19

discharge end 16 andthe: screen 1. Also, the slope of the feed chute 16 is adjustable through anangle so as to adjust the speed of travel of the ore. The suction tube 2 is rotatable'througha small-arc so asto adjust the a, which is the angle between a center line of the slot and a vertical through the center 'or axis. of the tube.

For small sizes, a tubular screen, illustrated in Fig. 4; may be merely a tubular screen 30 mounted on an 'end plate 31 to whicha shaft 32 is attached. A hearing mount 33 encompasses a portion of the shaft 32 and is arr ngedto be mo n e on a framework inte ti to hold the screen substantially horizontal; A pulley or sheave .34 pr s means tor rotatin th s r en ismnailed in the bearing housi g .33.. The screen of 11 619 should be substantial and heavy enough to support wn wei h or supported on a trams. and und r nsr n o ti ns the screen may vary from 1.6 to .299 $19- pending upon the particular ore being used sggeep may be attached to the end plate 31 by means. of screws 35, or any convenient means of mounting the screen securely on the .end plate; V i

, Where a longer cylindrical screen is desired, illustrated in Figure 5, a screen tube 36 is secured in a similar ma ner to the end plate 31, b11t' the opposite end of the screen rests on a roller bearing support which include a pair of rollers 78 on which the screen rests; and-as the screen turns the rollers 78 rotatably suppprt'the inner end of the screen. a t

"Where a long screen is used, a suction :tube 37 is .provided with a tapered slot 38 ,"Figure 6, so as to .provide a fairly even distribution of suction over the length of the screen. In this instance the tapered slot 38 has its" narrow portion 39 adjacent the connection to :themain suction line, while the wider e'nd of the slot 40 :is at the narrow end 41 of the suction tube 37. Normally the suction tube 37 is mounted on adjustable bracket 42 which is secured to a frame part 43. The adjustable bracket is arranged to permit a rotation of the tube through a small arcyto permit adjustment of the position of the slot in relation to discharge end of the feed chute.

A modified screen and suction tube assembly is illustrated in Figure'S, which is generally useful for short screen sections. In this case a screen 45 is rot-atably mounted on a suction-tube 46, substantially as described above. The suction tube 46 includes a wide slot 47 which has aforaminous bottom 48 and sidewalls 49 surrounding the slot in position tofbe adjacent to the screen. The

wide slot with the 'foraminous bottom provides means for-extending the area of suction over the surface of the screen, whichpis useful for verylight components.

The op ra on of t e .d v mayb l us rat d rie erencejto th'elschematic drawing of fFigure 1 wherein .a

'f e'db n 1 is arranged to introduce ore into @the feed chute;15 The ;-feed chute 15 is .arranged to be moved to an angle founfd desirable for the particular ore'being used. The ,chute 15 is positioned so that the oreissuing therefrom falls ,on the screen directly above the .slot 3 inthe upper suctiontuhe. f'Ihescreen 'is rotated as infdicated-by the arrow 52 and when suctionis applied to the tube} the light fraction o'fithe ote is held Q I the screen by thesuctiqn while'the heavierpqm qnents 'fall over the screen down. onto ,an intermediate chute 53which discharges. onto. a {feed chute .15 ,iorthe second .stageof the device. The. light fractions pass over the, crown or apex of...the screen. of-the first stage and fallIinto collector 7. TIheilight fractions .which dojnot fall. off the screen areblown-joi'fthymeans.ofgth ir..tuhe f5. {the ore passing ealolig 11 the intermediate chute 3 ntoj' the 'feed .jchute 15;.Jdfith.hSCQn 1 as .i ssuhieste stiQ' .9 4h andgstgge twilight-trac io heigse te at 9 2W.

I collector :7 of-thmsecond-stage- 'le theremainder of 7 d a ashl t thecorepasses'on, through the seeondeinterme 53aonto.th r. fi qhl e 1 J -th thirdst sei he r)" an le fractions from the third stage pass into a heavy fractions collector 55 which is discard'ed'or utilized as the case may double sheave 57 mounted onthe second stage to V-belt V sheave 34 of the first stage.--.The second stage is driven T y eans a e l sh. 6 me cqsnests between t double V-belt sheave 57 of the third stage and the double V-belt sheave 57 of the secondsta'ge." A motor 58 having a Vebelt sheave 59 mounted on its shaft is interconnected by means of a V-belt 61 to the double pulley 57 of the third stage providing motivating powerfor rotating all of the screens. An air pump 65, which may be any type of pump available to provide the. capacity needed for the operation of the device, is interconnected to a heade .66 which h s nected with suction 1 mount d on he d vice;

Th l sht'i actions are lle edirom he co lec r tube 8 y fa su tion rump, no show interconnected with an .outlet 70 on a collectorand separator drum 71 which acts as a separator from he nd the light fractions- Aheader72 connected to the dr m ha a plurality of leads 73, 74 and 75 interconnected w th the collector tube .of .each stage. V In typical operation on amicapre having .8 mi a $9 tent of between and 60%,:theore is ground to about 20 mesh size, whichmeans that substantially a the ground ore passes a zoines'h screen; .Eaeho th screen 1 is a 40 mesh screen tube mo nted in posit on .forro ation over .a suction .tubeZ. The pump 5 :hassutficient capacity to ptovide a few pounds .d fierential air pre su between the outside and the inside o the scree so tha light material may .he zheldon ithescreen. The mice is stage collects mica in the co lecto Th firs st e collects ithe major portion of the mica trom the ore, and the t an p s ases-thatio iowni k up sub anti lly t e rest. grhe .concentrate obta ne from theco le tq t be 8 ntainsin excess of about 99% mice while t e t il discharged into the hopper .55 .eont inde s than 2% mica. 'The screen are rota ed a album 5. IFYQ HE PH PCITIDiDMtQIWithlhQ1Q .m91mt s .a. bout;30 tromihe crown of the screen- 'lh zdis hsme 29. m d within one and is hal in hes new (the is teen cr ng above the slot.

.By a justing th angl :14 in ithe 19 .4 2 of athe :feed. chute, and, als th d ta 9f; .abokethe slohyarioustypes of ore' maybe Ear.ezgamp aasbes sz em yh es na sts itro. no sangue by -.c.n shins th asbestss'. o and aw tin t e asbestos -i .hile thegang eldisrqari o tetmay; al o yzmsanac thed s wh n 3' sh o e is pa se et i he s reen -ln t i she th hea i uranium values are collected intheheavy frfactions hopper Wh le the light r tractions or gangue .are discarded. Any-of gLhC ores in which a crusts is formedonjthie" .sa s eanii whi hme m n r all s na b cr bbe e by m l nsmay: b rbenefis a e a zrgh dev Al where a classification of the recovered values is.desired, different-:coarseness of screen may. .used .on the difierent stagestoeijt'ectively.providea classification. While-the nce has been illustrated hyreference .to spe ific emb d m nts. ther e on t l m h inte, th

be separa ed ecise deta l s a ta l Pos coverings drnember and 7 .aaee lalet i i al f t st s .67, .58 and s2 intense fed intothe first sta e .from the hoppe and the firs distance therealong and mounted adjacent'to' and below the crown of said foraminous cylinder, means for applying suction on said slot so as to draw air only through said foraminous cover over said slot, feed chute means arranged for passing a thin spray of ore in a gravity fiow onto the foraminous cylinder above said slot, means for rotating said foraminous cylinder in the direction from said slot upwardly toward the crown thereof, and means arranged to collect light ore fractions carried over the crown of said cylinder.

2. Apparatus for the dry beneficiation of mineral values from their natural ores comprising at least one elongated horizontally disposed hollow member, a foraminous cylinder of larger cross sectional dimensions than said member covering said member and mounted for independent rotation thereon, a slot in said member extending a substantial distance therealong and adjustably mounted adjacent to and below the crown of said foraminous cylinder, means for applying suction on said member so as to draw air only through said foraminous cover over said slot, feed chute means arranged for passing a thin spray of ore in a gravity flow onto said foraminous surface covering said slot, means for rotating said foraminous cylinder in the direction from said slot upwardly toward the crown thereof, and means opposite said slot arranged to blow air through said foraminous surface to remove adhering ore components.

3. Apparatus for the dry beneficiation of mineral values from their natural ores comprising at least one horizontally disposed hollow cylinder, at foraminous screen cylinder covering said hollow cylinder and mounted for independent rotation thereon, said screen having a substantially larger diameter than said hollow cylinder, a slot in said cylinder extending a substantial distance therealong and mounted adjacent to the inner surface of and below the'crown of said foraminous member and in an upper quadrant thereof, means for applying suction to said hollow cylinder so as to draw air only through said foraminous screen covering said slot, feed chute means arranged for passing a thin spray of ore on said foraminous cylinder in position so that the dropping ore falls on the foraminous surface above said slot, means for rotating said screen cylinder in the direction from said slot upwardly toward the crown thereof, and means arranged to blow air through a narrow elongated portion of said surface to remove adhering ore components carried over the crown of the foraminous cylinder.

4. Apparatus for the dry beneficiation of mineral values from natural ores comprising a horizontally disposed screen cylindrical member mounted for rotation, a tube mounted in said screen member and arranged with a slot juxtaposed to the inner surface of said screen, said slot being disposed adjacent to and below the crown of said screen member, said tube being substantially smaller in diameter than the diameter of said screen member, means for applying suction to said tube so as to draw air through said slot and the portion of said screen member above said slot, means for dropping a gravity flow of a thin spray of ore onto said screen member above the slot in said tube, means for rotating said screen member in a direction from said slot upwardly toward the crown of said screen, and means for recovering light fractions of ore adhering to said screen member passing over the crown thereof.

5. Apparatus for the dry beneficiation of mineral values from natural ores comprising a horizontally disposed screen cylindrical member mounted for rotation, a tube mounted in said screen member and arranged with an elongated tapered slot juxtaposed with the inner surface of said screen and disposed adjacent to and below the crown thereof, said tube being substantially smaller in diameter than the diameter of said screen member, means for applying suction to said tube so as to draw air through said slot and the portion of said screen member above said slot, means for dropping a gravity flow of a thin spray of ore onto said screen member above the slot in said tube, means for rotating said screen member in a direction from said slot upwardly to the crown of said screen, and means for recovering light fractions of ore adhering to said screen member passing. over the crown thereof.

6. Apparatus for the dry beneficiation of mineral values from natural ores comprising a horizontally disposed screen cylindrical member mounted for rotation, a tube mounted in said screen member and arranged with a wide, walled slot juxtaposed with the inner surface of said screen disposed adjacent to and below the crown thereof, said tubebeing substantially smaller in diameter than the diameter of said screen member, means forapplying suction to said tube so as to draw air through said slot and v the portion of said screen member above said slot, means for dropping a gravity flow of a thin spray of ore on-said screen member above the slot in said tube, means for rotating said screen member in a direction from said slot upwardly to the crown of said screen, and means for recovering light fractions of ore adhering to said screen member passing over the crown thereof.

7. In apparatus for the dry beneficiation of mineral values from their natural ores in which a foraminous member is rotated over a hollow member with a slot closely juxtaposed to the inner surface of said foraminous member and arranged for drawing air through said foraminous member, the improvement which comprises a hollow member having a tapered slot therein with a narrow portion of the tapered slot adjacent the connection to the source of suction, and upstanding walls extending outwardly from said hollow member forming the peripheral boundary of said slot and arranged with the opening positioned closely adjacent the inner surface of said foraminous member.

8. In apparatus for the dry beneficiation of mineral values from their natural ores in which a foraminous member is rotated over a tube with a slot closely juxtaposed to the inner surface of said foraminous member and arranged for drawing air through said foraminous member, the improvement which comprises said tube having an elongated tapered slot arranged so as to permit air to be drawn through a portion of the foraminous member, upstanding walls extending outwardly from said tube forming the peripheral boundary of said slot and arranged to be positioned closely adjacent the inner surface of said foraminous member, and a foraminous bottom on said slot forming communication with said tube.

9. Apparatus for the dry beneficiation of mineral values from their natural ores comprising a horizontally disposed, hollow foraminous cylinder arranged for rotation, a suction tube of substantially smaller cross sectional dimensions than said foraminous cylinder disposed therein and having means for its connection to an air pump for reducing air pressure therein and draw air through a portion of said foraminous cylinder, there being a slot having upstanding walls bordering the same in said tube mounted closely adjacent to and extending substantially along the length of said foraminous cylinder, means for adjusting the angular position of said slot in relation to said foraminous cylinder, feed launder means adjustably arranged to drop a thin spray of finely divided ore in a gravity flow onto the outer surface of said foraminous cylinder above said slot, means for rotating said foraminous cylinder in a direction from said slot upwardly toward the crown of said cylinder, discharge means arranged adjacent the foraminous cylinder at a position opposite said slot and mounted for collecting light fractions of ore carried over the crown of said foraminous cylinder, and means for removing adhering light fractions on said foraminous cylinder. 7

10. Apparatus for the dry beneficiation of mineral values from their natural ores comprising at least one horizontally disposed hollow member, an endless, movable foraminous member covering a portion of said hollow 

